Engine synchronizing mechanism with hydraulic actuation



Feb. 7, 1961 s B. TAYLOR 2,970,442

ENGINE SYNCHRONIZING MECHANISM WITH HYDRAULIC ACTUATION v Filed July 9,195s United States Patent F ENGINE SYNCHRONIZING MECHANISM j HYDRAULICACTUATION l S'Blackwell Taylor, Cleveland, Ohio f (21850 S. WoodlandRoad, Shaker Heights 22, Ohio) Filed July 9, 195s, ser. No. 747,469 1oclaims. (cl. stl-54.6)

This invention vrelates to speed synchronizers for en'- gines and moreparticularly to :a mechanlsm for controle ling the speed of a slaveengineJ according to thel speed device for the slave engine toV increase.or vdecreasefthe speed thereof whenever the speed is lesser or greaterthan the speed of the master engine.

It is another object to provide an engine speedfsynchronizing meanshaving means for detecting differential speedsbetween two engines andemployingahydraulic actuator which is directly responsive to suchdifferential speed detectorfor operating a hydraulic servo motor whichin turnoperates a speed control device for one of the engines to bringit into synchronism with the other engine. Y

Another object to provide atspeed synchronizer for a master engine and aslave engine in whichvcumbersome rods and linkagesbetween a speeddifferential responsive device and a speed control device for the slaveengine are eliminated and an easily `installedrand maintained hydraulicimpulse mechanism-is substituted.

v Another object is to provide an engine speed synchronizing device. ofthe type described in which a means is provided for disconnecting thedevice from the engines so as to render the same inoperative, the'disconnecting means being automatically operable under predeterminedconditions and/or being manuallyy controllable.

Other objects ofthe invention will be apparent from the followingdescription and from the drawing in which:

Figure 1 is a semi-diagrammatic illustration of vthe synchronizingarrangement and withsome ofthe parts shown in cross section. f

Figure 2 is a fragmentaryview o f an optional form of the device.

In the synchronizing .arrangement illustrated, either engine 10 may bethe master engine whose speedymay be controlled by an operator or bysome automatic means and engine 11 is a slave engine whose speed iscontrolled by the synchronizing mechanism vaccording to the speed of themaster engine, or 11 may be the master engine and 10, the slave engine.It will be understood that if engine 10 is the master engine, the lever12 is part of the throttle or other speed control device for the engine1-1, whereas if engine 11.is the master engine, the lever -12 ise'partof the throttle or other speed control device of the engine 10. In thefollowing description it will be assumed that engine 10 is the masterkengine and the lever 12 is part of the speed control device of theslave engine 11. i

The speed synchronizing lmechanism includes .a combination differentialspeed detectorand hydraulic actuator-'generally designated as 13. Thisunit Yhas, av base or.y housing member 14 in which a cylindricalmember"'15 -retatablymounted. The' cylindrical' member 15' 1121.5l

2,970,442 Patented Feb. 7, 1961 ICC agcylindricalbore'16 which isthreaded at one end. The cylindrical member 15 is joumalled by bearings17 and V13 in the housing 14 for rotation therein. One end of the bore16 is closed by a plug 19 which is fixed to the housing 14 by screws 20and which has an extension 21 which `closelyvfits the bore 16 and issealed thereagainst by a packing 22. A duct 23 in the plug 19 leads fromthe bore 16 to the exterior of the cylindrical member 15 andcommunicates with a pipe 24 connected to the plug k19 by a suitablecoupling 25.

f The bearings 17 and 18 are preferably press fitted within thehousing14 rand onto the cylindrical member 15 so that the latter will berestrained from longitudinal movement alongthe axis of the threaded bore16.

.A member 26 has a central threaded section 27 .which is threadedy intoa cylindrical member 15. Extending from the threaded central section 27is a rod 30 which termiatesin a piston 31 having a close sliding fitwithin the-bore 16 and which is sealed thereagainst bya packing-'32.` I

QThe cylindrical-member 15, the threaded member 26, and plug 19cooperate to form a hollow structure which I includes a sealed uidchamber 65. -The piston 31 forms Va-inovfable wall of the chamber whichis sealed by packing 32 in the piston. l `rAt the other -end of thethreaded member 26 there is ars'haft 33 which extendsthrough a'closurecap 34 for thejhousing 14. The outerendof the shaft 33 has a groove 38to receive a tongue 35 on a exible shaftv36. The shafts 33 and 36 aresecured together by..a suitable couplingv 37. The flexible shaft 36 isconnected to the slave engine 11 for rotation thereby by means of vaclutch 39. Mounted in the housing 14 is a driving gear 45 having a keyedconnection 146 with a shaft 47. The latter is journalled for rotationwithin the housing 14 and cap 34 by bearings 48 and 49 and one end ofthe shaft ex tends through the closure cap 34 and is connected to lallexible shaft by a coupling 51 similar to that used in connecting shaft33fto exible shaft 36. The flexible shaft 50 has its other end connectedto the master'engine 10 for rotation thereby, by-means of a clutch40.

The driving gear 45l meshes with an idler gear 55 which has a keyedconnection'56gto a shaft 57. VThe latter is journalled for rotationWithin the housing 14 and closure cap 34 by bearings 58 and 59. i n Theidler gear alsomeshes with a driven gearg61 l formed integrally on thecylindrical member 15. Each yshown in diagrammatic fashion.

of the gears 45, 55, and 61 has a lixed longitudinal position withintheV housing.

' The pipe 24 leads from the plug 19 to onel end of conventionalhydraulic servo motor 63, the latter being The servo motor has a piston64 and a piston rod 65 which is attached to a leverl 12 which may haveone end pivotally connected to a suitable stationary support 66 andwhose other end operates the throttle or other speed control device forf the slave engine 11. The servo motor 63 operates ina wellV knownmanner, the rod 65 being extended when fluid under pressureis forcedinto the chamber 67 and- L' energized andnlisengaged when the solenoidis energized.;

althoughy the 'reverse arrangement may be provided ifsq desired."I ,Inthe latter case the open and closed positions Vls vswitches are reversedfrom those described 1f9PraPinel-Phaa In addition,automaticoperationofthe clutches by the 'solenoids is provided by means of switches 53 and54. These switches are operatedbycontact with, a collar 6l] attached-to`the shaft 33 by a loclnvut'7t)` or other suitable means. -They arenormally'open and'when closed by contact with Ythecollar-60 cause thesolenoids 42 'and 43 to become energized,forwdisengaging the` clutches39 and 40. If desiredt he caps 34 may be extended fartheralong the shaft33 to enclose the collar 60 Yand switches 53 andr54.V Y

A normally closed manually operated overriding switch 71 vris providedso that the solenoids may be de-energized for engaging `the clutcheseven though either of the switches 53 c1554 are closed. Also, a manually`controlled normally jopen switch 52 -is provided for causing engagementor disengagement of the clutches.

'In operation, the mastervengine 10 has its speed con# trolled in anydesired manner, such as by a manual or automatic pilot controlledthrottle. While the solenoid 43 is de-energized so that the clutch 40 isengaged, engine 10 `rotatesthe flexible shaft 50 in any desired ratio tothe speed of the master engine. The flexible shaft 50 drives the shaft47 which in turn rotates the driving gear 45. The latter rotates theidler lgear 55 which in turn rotates the driven gear 61 and hence the'cylindrical member 15. Due to the interposition of the idler gear 55,the cylindrical member -rotates in the same direction as the llexibleshaft 5,0.,

At Vthe same time, the flexible shaft 36 is rotated by the slave engine11 while solenoid 42 is de-energized and clutch 39 is engaged and inturn rotates the threaded member'z. The ilexible shaft 36 rotates intheusame direction as the flexible shaftS and hence the threaded member26 rotates vin the same direction as the cylindrical member 15. Thellexible shaft 36 preferably rotates with the same ratio to the speed ofa slave engine '11 asthe exible shaft 50 with respect vto the masterengine 10. With this arrangement, the driving gear 45 has -a one to oneratio with the driven gear 61 and hence the threaded member 26 willrotate at the same speed as the cylindrical member 15 when the masterand slave engine are rotating at identical speeds. If the speed ratio ofthe exible shaft 50 with respect tothe master engine 10 is differentthan the ratio for the flexible shaft 36 withvrespect to the slaveengine 11, a corresponding ratio must be provided between the drivengear 61 vand thedriving gearl 45 in order to have the cylindrical member15 and the threaded member 26 rotate at `the same speed when the masterand slave engine are rotating at identical speeds.

When the two engines are rotating at the same speed, the threaded member26 retains its longitudinal position within the cylindrical member V15and hence the piston 31 remains in a fixed longitudinal position withinthe bore 16. As aresult, the servo motor piston 64 is also maintained ina fixed position and it in turn maintains the throttle lever 12 in a setposition.

If the speed of the master engine drops below that of the slave engine,the cylindrical member 15 will rotate ata slower speed `than thethreaded member 26 and, as-y surning a right handed threaded connectionbetween members 26 and-15, the member 26 will thread itself leftwardlyfurther into the cylindrical member 15. In doing so, the piston k31forces some of the uid from the chamber 65 through the pipe 24 into theservo motor chamber 67 to move the piston -64 rightwardly and-the upperend of the lever 12 leftwardly. This will cause `the speed controldevice operated by the lever L12 to decrease the speed of theslaveengine 11 nntil such time `that it is again in 'synchronism with .themaster engine, at 4which 4time the rotative speeds of the members 15 and26 will again co-` incide-and relative longitudinal motion therebetweenwill cease Var1"c,lthelever '12 will be heid in -a set position.

I-If the ,speedrof'the master engineis increased, the cylin 'dr-icalmember 15 lwill be'rotated at a'higher speed than the threaded memberG26.:V "If the 'threaded connection -between the two membersv is formedwith a rightr hand thread, the member 26 willfstart to unthread from thecylindrical member 15 and h'ence move longitudinally in a right handdirection as viewed in the drawing. This rectilinear movement isimparted to the piston 31 to increase the volume of theuidfchamber 65which permits someof the uidwithin theservo motor chamber 67 to beforced -through the pipe24 into. the chamber 65 by the action of thespring 68. This moves the upper end of the lever 12 to the right-tochange the setting of the throttle or other speed control device forslave enginell in such a manner as to` increase the speedthereof. Whenthe speed of slave engine 11 catches up with that of master engine 10,the cylindricalmemberl andthe threaded member 26 will again rotate atthe same speed and the relative rectilinear motion therebetween willcease and the position of the lever v12 will again be maintained in aset position. lf the threaded connection between the members 15 and 26is lefthanded, the direction of movement of the threaded member 26,piston 31, servo motor piston 64, and lever 12 will be reversed fromthat described above and such reverse movement of the lever 12 must becoordinated with the throttle to correspondingly properly increase ordecrease the speed of the slave engine.

` In the event the slave engine 11 gets out of synchronism with masterengine 10 and for any reason is not able to achieve synchronismbeforemem'ber 2.6 has reached the end of its stroke in either directionas required for obtaning synchronism, the collar 60 will contact thecorrespond* ing switch 53 or 54 to energize thev solenoids 42 and 43 anddisengage `the clutches 39 and 40. This protects the device against damageby 'stopping rotation of .the parts 26 and 15 so as to preventovertravel of the member 26.

If either of the switches 53 or 54 has thus been closed by collar'60,the device may be made operable again by opening the overriding switch71 until the collar 60 moves away from the particular switch 53 or 54and allows the same to open. The switches 53 and 54 may be mountedadjacent the device 13 on any suitable base or support, or may bemounted on or within the device 13.

`It may .be desirable at other times, as when starting the engines, orwhen operating only one engine, to render the speed synchronizing deviceinoperable. This is accomplished by closing the manual ,switch 52 toenergize the solenoidsand hence disengage the Vclutches 39 and 40.Figure 2 shows a fragmentary portion of an optional form of the device13 in which the idler gear 55 of Figure l is omitted. VIn such case theshaft 47a must be so connected to the master engine 10 that it rotatesin the opposite direction of shaft 33. This may be accomplished invarious ways, such as by gearing at the power take oil for the engine10, locating the power takeoff at the opposite end of the engine 10,extending the shaft v47a through the housing 14a and driving the shaftfrom such extension, etc.

Although the; embodiment of the invention shown in the drawingaccommodates onlyone slave engine,it will be understood that theinvention can be readily modified to control two or more engines withrespect toa master engine. Thus, for each vadditional engine to becontrolled, anotheridler gear similar to gear 55 may be provided to meshvwith driving gear 45 and drive another cylindrical. membercorresponding to member 15, which in .turnwill Vfunction lwith another.threaded -member corresponding to member A26 to operate another servomotor corresponding to motor 63for controlling the throttle oftheadditional engine. i

Obviously, additional changesmay be made in the particular form of theinvention withoutdepartingfrom the inventive concepts covered .by thefollowing claims.

I claim; Y

l. A ,hydraulic `actuator comprising a .61st-member connectibletoanlengine for rotationpthereby.a second member comestible@anotherenaiaafor rotation there by, said members forming a sealedchamber for duid,

fo-Ilm.

one of said members forming a movable wall of said chamber, said membersbeing cooperatively arranged so as to move relative to each other inresponse to a diterential in their rotative speeds to cause said Wall tomove relative to the other member for changing the volume of saidchamber in accordance with said speed differential, and a duct leadingfrom said chamber through which fluid may be introduced into or expelledfrom said chamber as the volume of the chamber is varied.

2. A hydraulic actuator in accordance with claim 1 in which thecooperative engagement of the rst and second members for movementrelative to each other in response to a dilerential'in their rotativespeeds comprises a threaded nterengagement of said members.

3. A hydraulic actuator in accordance with claim 1 in which thecooperative engagement of the trst and second members for movementrelative to each other in response to a differential in their rotativespeeds comprises a threaded interengagement of said members and thechamber and the movable wall are coaxial one with the other and withsaid threaded interengagement of said members.

4. A hydraulic actuator in accordance with claim 1 in which the chamberis cylindrical and the movable wall is in the form of a cylindricalpiston carried by one of the members and movable in the chamber.

5. A hydraulic actuator comprising a housing, a cylindrical memberrotatably supported in said housing and having a bore therein providinga chamber for Huid, closure means for one end of the chamber, a secondmember rotatably supported by said cylindrical member and having aportion in sealed engagement therewith, said portion providing a movablewall at the other end of said chamber, a duct through said closure meansand leading from said chamber to the exterior of said cylindricalmember, means associated with each of said members whereby said membersmay be rotated independently of each other, means interconnecting saidmembers whereby a differential in their speeds of rotation when rotatingin the same direction will cause relative rectilinear movementtherebetween whereby said movable wall will move toward or away fromsaid chamber to decrease or increase the volume of said chamberdepending upon which member is rotating the fastest.

6. A hydraulic actuator in accordance with claim 5 in which saidinterconnecting means comprises a threaded engagement between saidmembers at one end of said cylindrical member.

7. A hydraulic actuator in accordance with claim 5 in which said closuremeans is non-rotatably attached to said housing.

8. A hydraulic actuator in accordance with claim 5 in which saidcylindrical member is supported in said housing for substantially nomovement with respect to said housing along the axis of rotation of saidcylindrical member.

9. A hydraulic actuator in accordance with claim 6 in which saidcylindrical member is fixed against movement along its axis of rotationwith respect to said housing and said second member has a shaftextending from said housing, said shaft being extendable and retractablewith respect to said housing as said second member moves rectilinearlyrelative to said cylindrical member.

l0. A hydraulic actuator comprising a housing, a cylindrical memberrotatably supported in said housing in a fixed position longitudinallyof the axis of rotation, said cylindrical member having a bore therein,one end of said bore being closed by a plug which is non-rotatablyattached to said housing, the other end of the bore being threaded andan intermediate portion of the bore being smooth, a second memberrotatably mounted within the housing and having a central portion inthreaded engager ment with said threaded bore so as to be movablelongitudinally of said cylindrical member when said members are rotatedat different speeds, a piston carried by said second member andlocatedwithin said intermediate smooth bore portion, said piston beingspaced from said plug and sealed with respect to said smooth boreportion so as to form a sealed chamber for fluid Within said bore andconstituting a movable wall for said chamber to increase or decrease4the volume thereof, a duct through said plug in communication with saidchamber for permitting expulsion or admission of fluid from or to saidchamber as the volume of the latter is decreased or increased, a drivengear carried by the cylindrical member whereby the latter may berotated, an idler gear journalled in said housing and in mesh with saiddriven gear, a driving gear journalled in said housing and in mesh withsaid idler gear, said driving gear having a shaft zextending from saidhousing whereby said driving gear may be rotated, said idler and drivinggears having a fixed longitudinal position within said housing, saidsecond member having a shaft whereby said second member may be rotated,said shaft extending from said threaded central section to the exteriorof the housing, said piston being longitudinally movable with saidsecond member for decreasing or increasing the volume of said chamber.

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